Hi,

Here is a Youtube video that show the problem: https://youtu.be/CWlmpoZ6YFw

The players used in the video are MPC-HC and PotPlayer.

These players are configured to switch to full screen mode when I double-click in the video. It's not their default behavior.

But it's not specific to these two players. I can reproduced by using Movie & TV, WMP and VLC. Just ensure that the always on top feature is active/you will be able see the player window and double-click on it.

Reproducible by using any WB theme.

Reproducible by launching a game/program that support window/fullscreen mode (I can reproduce it with Anno 1800)

The steps in the video:

1. launch the playing of a video in MPC-HC
2. set the focus to Windows Explorer in the taskbar (or another program)
3. double-click on the MPC-HC window
4. stay in full screen for at least 6s and then double-click on the MPC-HC window to exit the fullscreen mode =>the buttons are not skinned correctly
   
5. set the focus to Firefox in the taskbar (or another program)
6. do the step 3 and 4 again => same result
7. move the MPC-HC taskbar button at the first place and repeat steps 2, 3 and 4 => the number of impacted buttons is different
8. set the focus to MPC-HC in the taskbar and repeat step 3 and 4 => all the buttons are skinned correctly
9. Pause MPC-HC and launch the playing of a video in PotPlayer
10. double-click on the PotPlayer window and do the step 4 => all the buttons are skinned correctly
11. repeat the step 2
    
12. repeat the step 10 => same result as after the step 4.

Windows 10 Enterprise (19041.vb_release.191206-1406)
WindowBlinds 10.87 (062 - Windows 10 Edition) - 64 bit OS

Same result on my other PC

Windows 10 Home (19041.vb_release.191206-1406)
WindowBlinds 10.84 (059 - Windows 10 Edition) - 64 bit OS